in reply to GD @ 300dpi output

You are confused. An image contains pixels. Those pixels only become dpi when you print them. GD, has nothing whatsoever to do with printing.

The exact, bit for bit, binary identical, same image can be printed at 72 dpi or 300 dpi or 1 dot per metre if you want it really big.

A 2550 x 3300 printed at 72 dpi will be 35.416" x 45.833". The same image printed at 300dpi will be 8.5" x 10". The content of the image file doesn't change at all.

What is telling you that the images produced using GD are "72dpi"?

Looking again, I see you are outputting to jpg format. That is the wrong thing to do if you want to retain quality.

For more information about the confusion that Photoshop creates, read:http://proshooter.com/article_whatisa300dpiJPeg.htm (You'll just have to forgive the photographer the hideous layout:) the information is good.)

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